1. Field of the Invention
The present invention relates to a sheet processing technique to perform a specific process to a sheet.
2. Description of the Related Art
In a conventional sheet processing apparatus for performing a staple process and a folding process, there is known a structure including a stapler to perform the staple process to a sheet, a pair of folding rollers and a folding blade to perform the folding process to the sheet, and a switchback transport unit to transport the sheet to the stapler or the pair of folding rollers.
In the conventional sheet processing apparatus as stated above, for sheet removal in the case where a sheet jam (sheet jamming) occurs and for maintenance, there is known a structure in which only a portion including a transport guide constituting a sheet transport path to hold a sheet at the time when a specified process is performed by the pair of folding rolls or the like and the stapler can be pulled out to the outside of the sheet processing apparatus, or a structure in which only the vicinity of the pair of folding rollers can be pulled out to the outside of the sheet processing apparatus. In the conventional sheet processing apparatus having the structure as stated above, it is general that for example, a transport guide constituting a transport path to perform switchback transport is opened in a state where it remains in the sheet processing apparatus and a jammed sheet is removed.
However, even if the transport guide is opened in the sheet processing apparatus, it can not be said that a sufficient space for sheet removal is obtained only by that, and there are many cases where the sheet removal is difficult.